Improvement in calculating-machine



dntcd tzitc JOHN HERMANN RUDOLPH REFF'ELT, OF HOBOKN, NEW JERSEY.

Letters Patent No. 94,77 2, sated Septemberll, 1869.

IBIIPROVEMENT IN CALCULATING-MACHINB.

Tle Schedule referred to in these Letters Patent and making part of the same.

To a-ll whom it may concern Be it known that I, JOHN HERMANN RUDOLPH REFFELT, of' Hoboken, in the county of Hudson, and State of. New Jersey, have invented a new and improved Calcnlating-Macbine; and I do hereby declare that the following is a full, clear, and exact description thereof, which will enable others skilled in the art to make and use the same, reference being had to the accompanying drawing, forming part of' this specitication, in which Figures 1 and 2 are face views, partly in section, of my improved calculating-machine, showing opposite sides of' the same.

Figure Y3 is a central section of the same.

Similar letters ofref'erence indicate corresponding parts.

- This invention has foi` its object to provide an ap# params by means ot' which either one of the four rules of arithmetic, viz, addition, subtraction, multiplication, and division, can be successfully exercised for practical and educational pui-poser.

The invention consist-s chieliy in the arrangement of a disk, orturn-table, working between 'two slotted disks, or plates, and carrying a system of figures and' A, in the drawing, represent-sa circular plate, made of sheet-metal or other suitable material, of' suitable diameter. It is, by a central pin, a, pivoted to and between two plates, B and C, which are arranged in an annular frame, D.

Diametral cross-bars E, on both sides of the frame v D, serve to hold the various plates, or disks in their respective positions and to support the pivot a.

The disk Acan be freely turned on the pivot, while the other two plates, B C, are fixed. The diameters of' the plates B C are smaller than that ofthe disk A,

' so that an annular port-ion of the latter disk remains visible between the edge of each plate B C and the frame D. "his annular portion is divided into one hundred equal parts, and has the divisions indicated by one hundred dots on both sides.

In order to obtain better control and account ot' thc dots, the frame l) has, ou one side, also been divided into one hundred spaces, and cach space marked with o.- iigurc, the figures being in regular succession from one to one hundred, as in Iig. 1.

The other eide oi' thc frame is not subdivided, but in its place the dots ou the plate A are marked directly, as in fig. 2, with figures from one to one hun- -number of' such dots, figures, and subdivisions cau-be varied at will.

The plate B has two apertures, b and c, cut through it. 'Each of these apertures is above a separate circular line of' figures written upon the f'uce ofthe plate A. These two circles contain the figures, ii'om one to one hundred successively, written in opposite directions, as is clearly shown in fig. v1. The iigures'undcr the aperture b are written in the same order as those on the frame D, while those under the aperture c are written in reverse order.

The dots through the plate A may, as shown, be in the shape of small holes, each apt to receive a pin, or handle. One of these small holes, d, is marked by a cross or crosses, or otherwise, as shown in fig. 1.

\\"hen it is brought against the bar E, the figures o will be visible through the apertures b c. When figures are to be added, the pin, or handle is placed into that dot, or small hole, which is opposite the ligure ou the flume representing the number to bc added. Thus, if the apparatus stands at zero, with the crossmark zZ at the bar E, and if' the .figure 12 is Ato be added to l5, the handle is first placed into the hole opposite 12, on D, and then the disk A is turned until the handle strikes the bar E. The figure 12 is then visible through b. Then the handle is fitted into the hole opposite 15, on D, and carried to the cross-bar, when the plate is turned fii'teeii-one-hundredths more parts, of' its circumference, whereby the figure 2T is brought under the aperture'b. Thus addition can be carried on indefinitelyy and accurately. The hundreds can be marked olii` by the counter, or may be recorded by a supplementary apparatus. Y

For subtracting, the said procedure is followed: The figure 9S), being supposed to be under the aperture c, and the figure 10 to be subtracted, the handle is placed into the,hole opposite 10, on D, and is carried against E, inthe same direction in which it was formerly turned, 'l'. c., in the direction of the arrow in fig. 1. As the iigures on thc subtracting-circle stand in the reverse order to those ot' the frame D, the value carried under c will be so much less than that formerly there, as the value carried by the handle represented when the handle was applied.

The other face of' the plate A is, where` it. is cov# ered by the plute C, divided into twelve, or more or less concentric rings, and each ring divided into one hundred, or more or lcs's equa-l spaces. The innermost ring contains the figures ii'om 1 to 100, in regular succession. 'lhc next contains those figures from 2 to 200, which are divisible by, 2, in regulalssueccssion; the next, those from 3 to 300, divisible by 3; the next, those divisible by 4, and so forth, the outermost ring in tig. 2 being represented to contain, in regular suc- ,one above eaohpf the twelve rings,

cession, those figures between 12 and A1,200 that are divisible by 12.

Through the plate O are eut twelve apertures, f, each large enough to display one division of eaclrriug. The gures on these rings are so arranged that when the figure 1, on the outer annular visible part e of the plate A is brought against the cross-bar, as in iig. 2, the figures displayed through the apertures f will be the results of the multiplication of said ligure 1 with the figures from 1 to 12 respectively.

The quotients are marked ou the plate C, near the apertures f. Thus, when any figure on the part e is brought against the cross-bar, the results of multiplication of the saine with me of the figures from 1 to 12 will appear.

For them ulti plication of larger numbers, the amounts are divided, so that when, for instance, 123 is to he multiplied -by 5,689, the latter ligure is first multiplied by 12 and then by 3, and the results put together and added in proper manner.

Division is produced on the same table. Suppose 108 is to be divided by 12. rlhe latter ligure is carried to the eross-bar,when one of the figures displayed through the apertures f will be 108, and the figure placed alongside oi' such aperture upon the plate C will be the quotient sought for,

When 56,000 is to be divided by 14, the latter figure is brought against E, when, through one aperture,

f, the figure 56 will appear opposite to the quotient 4.

The addition of the three naught-s will produce the true quotient, 4,000. l

Having thus described my invention,

What I claim as new, and desire 'to secure by Letters Patent, is-

lhe turning disk A, arranged between the stationary plates B G, attached to the frame D by means of the cross-bars E, when the same is provided with the dotted outer part, the tivo adding and subtracting-cir- 'cles on one side, and the multiplyingand dividing eir cleson the other side, as herein shown and described, for the purpose set forth.

' J. H. RREFFELT.

Witnesses:

FRANK BLooKLEY, C'. L. Topman. 

